Use strict & warnings. Fix several minor bugs uncovered by it.

Use strict & warnings.  Fix several minor bugs uncovered by it.

Semantics of assigning to $[ changed in Perl 5, and its use is `highly
discouraged'.  Programs obviously assumed $[ affects all arrays, but
it doesn't in Perl 5.  If these programs ever worked, then certainly
not with Perl 5.  Remove the assignments and shift indexes
accordingly.